Oil burner



A. P. LIVAR Oct. V17, 1944.

OIL BURNER Original Filed March 11, 1940 IN VEN TOR. FZZer( 7? van BY JVM/Mod,

Patented Oct. 17, 1944 oIL BURNERV Allen I. Livar, Dayton, Ohio, assignor to Chrysler Corporation, Detroit, Mich., a corporation of Delaware f Original applieatonMarch v11, 1940, Serial No. 323,375. Divided and this application January 27, 1941, Serial No. 376,115

1 Claim.

This application is a division of Serial No. 323,375 of Allen P. Livar, for Oil burner, filed March 11, 1940, now Patent 2,301,060, of November 3, 1942.

Specically the invention comprises a pressure atomizing oil burner including a `blast tube into which air is directed tangentially and forwardly at diametrically opposite points so -as to produce a whirling stream of air into such tube.

An object of the invention kis to provide means for adjusting the point of impingement cone of fuel spray and a rotating cylinder of airv issuing Afrom the blast tube, to provide for this purpose a cone which at all positions of adjustment will insure this body of air striking the cone of oil spray at the same distance from the nozzle orilice, and to provide means for manufacturing the cone in a position normal to the longitudinal axis of the blast tube.

Other objects of the invention will Vbe more apparent from the following description taken in connection with the accompanying drawing, wherein: y

Fig. 1 is a vertical sectional view through a burner embodying the invention. v

Fig. 2 is a transverse section taken on line 2-2 of Fig. 1.

The improved burner is described in detail in the aforesaid patent and in so far is pertinent to the present invention comprises a principal casting, generally designated by the numeral I9, including parts of the blower housing or housings, one such part being shown at II; blower outlet or outlets, one of which is shown at I2; and

a blasttube I3. A hood I4 is supported on the `part II and encloses the power assembly comprising' blower wheels (not shown), motor v.I5 and pump I6 which are connected by a belt II and mounted on a supporting plate I8. 'I'he hood also encloses a transformer I9 and its hinged mounting plate 20. The protective closure 'formed by the hood I4 has an opening at the bottom adjacent the rear end of the blast tube which is partially blocked by the transformer I9 and a further opening at the front Vabove the top of the blast tube which is partially The fuel pump I6 is suitably connected with a supply line (not shown) and has a pressure regulatory device 24 to which is connected a tube 25 leading to the nozzle. The tube 25 is adapted to extend downwardly between the hood I4 and the outer edge of the transformer mounting plate and thence upward through an opening 26 provided in the plate Y20 to connect with an -elbow 2'I on a short section of pipe 28 projecting rearwardly yfrom the recessed central portion '29 of a blast tube closing cap 30. A passage 3l is drilled through the portion 29 and a nozzle supporting tube 32 extends through the blast tube I3 from the passage 3| and supports the nozzle 33 at its outer end. The elbow 21, tube 28, cap

v3Il, tube 32, and nozzle 3S are assembled with an air volume adjusting damper 34, electrodes 35, and three-legged centering -spider 36 to complete a nozzle assembly which is removable as a unit from the blast tube I3.

' The power assembly supporting plate I8 is supported principally by resilient bumpers 31 fastened to the lower end of the supporting plate Vand resting in an inverted channel member 38 carried` by the blower housing. The center o'f gravity of the power assembly is preferably to the rear of the member 38 and the plate I8 isrestrained fromv tipping rearwardly by a bolt 39 mounted in a boss 4i!V on the tube I3. The upper end of the bolt 39 is provided with a nut 4I and is enclosed in a flanged spacer 42.

The transformer I9 is provided with inwardly extending insulators, one of which is shown at 43, surrounding transformer terminal contacts 44 which are spaced above the center of the blast tubev I3 and at each side of the centerline thereof substantially in line with but above the rear ends of the electrodes 35. The electrodes extend through the recessed central portion 29 of the blast tube cap 3D, being insulated therefrom by insulators 45 and retained in adjusted position thereon by a clamp 46. The rear of the electrodes are threaded to clamp thereto, as by suitable lock nuts, the lower end of the leaf springs, one of which is shown at 4'I made of a conductive, resilient material such as phosphor l bronze. The free end portions of the spring 41, which constitute nozzle assembly contact members, are in such position as to be engaged and by, there is provided the adjustment damper 34 which is cylindrically shaped and rotatably mounted in the blast tube .I3 having such clearances therewith as to permit rotation thereof but not undue leakage thereby. The cylinder is provided with a rear flange 48 which is rotatably journalled on the trunnion provided by the inwardly recessed portion 29 of cap 30 and which abuts the inner face of the flange of the cap. The cylinder is provided with a pair of longitudinally extending openings 49 and 50 respectively at the bottom and top thereof. Rotation of the cylinder effects a change in the volume of air admitted to the blast tube I3.

In order to rotate the cylinder the flange of the cap 3D is provided with an arcuate slot 5I of such length as to limit rotation of the damper between selected eXtreme positions. The stem of a thumb screw 52 extends through the slot 5| into the flange 48 of the cylinder and also through an adjusting lever 53 pivotally mounted on the section of tubing 28 and retained thereon by the elbow 21. The lever 53 may be shifted by releasing the screw 52 to adjust the damper 34 and hence the quantity of air admitted to the tube. This adjustment can be made during operation of the burner.

The construction of the damper 34 provides simultaneous and equal adjustment of the air streams and by regulating the volume of air at the outlets of the blowers the air stream is free from pulsations Which are present when the control is at the blower inlet.

In order to obtain further adjustment of the flame characteristics there is provided means for adjusting the point of impingement of the cone of fuel spray issuing from nozzle 33 and the rotating cylinder of air issuing from the blast tube. As clearly seen in Fig. 1 the end of the blast tube is partially obscured by an end cone 54 having a central aperture large enough to permit the cone of spray to issue therethrough without impingement, but the diameter of which aperture is substantially less than the diameter of the blast tube. The inner surface of the end cone is curved so as to restrict the rotating cylinder of air without interfering with the rotation thereof and the angularity thereof is such as to direct the air through the cone of spray for intimate mixture therewith a short distance beyond the end of the blast tube. The end cone 54 is an important adjunct of the oil burner since it controls the point of mixture of the fuel and combustion supporting air; hence the longitudinal spacing of the orifice of the end cone from the orifice of the spray nozzle is important and changes thereof regulate the thoroughness of combustion and adjust the shape of the flame to various shapes and sizes of reboxes. It is also necessary to adjust the end cone for different spray nozzles, there being nozzles available having different angles of spray.

In order to adjust the end cone while the oil burner is in operation, the end cone is provided with a cylindrical guiding ange 55 loosely fitting the interior wall of the blast tube I3, and*` it is attached at its lower extremity to a bar 56 extending along a channel or groove l at the bottom of the blast tube, which channel is provided for the purpose of maintaining the outer edge of the end cone exactly normal to the longitudinal axis of the blast tube so that the cone of air strikes the cone of oil spray at the same distance from the nozzle orice at all points. The channel or groove 5l terminates at its rear end in a shoulder 58 which acts as a limiting abutment by engaging a bend 59 in the rear end of the bar 5B. Immediately adjacent the bend there is attached a threaded member 60 which extends downward through a longitudinal slot 6I in the bottom of the draft tube. The horizontal, free end B2 of the barcloses the portion of the slot 6I to the rear of the threaded member 60 and a small channel-shaped member 63 loosely mounted on the threaded member 60 c loses the portion of the slot 6I in advance of the threaded member 60. A wing nut B4 is screwed onto the threaded member 60 to retain the channel member 63 and to clamp the bar and channel member in adjusted positiongso as to block the slot 6I against leakage and retaln-the end cone 54 in adjusted position. The nut 64 is placed immediately in advance of the standard upon which the burner rests so as to be available to the operator for substantially simultaneous adjustment of the damper 34 and the cone 54.

In operation the motor I5 drives the pump I6 causing fuel to be forced through the tube 25 and the tube 32 and to be sprayed through the nozzle 33. Simultaneously air is drawn upwardly around the transformer I9 and around the motor I5 into the blower inlet where the blowers force it downward, then tangentially into the blast tube at the upper and lower points to create a spiralling cylinder of air pressure. This body of air moves forward and is caused to be discharged through the cone of oilV spray by the end cone 54, a spark being simultaneously created by the electrodes 35 which ignites the fuel and air mixture.

Having described a preferred embodiment of my invention it should be apparent to those skilled in the art that the same permits of modifications' in arrangement and detail. All such as come within the scope of the following claim are considered a part of my invention.

I claim:

In an oil burner of the pressure atomizing type including a blast tube, blower means for forcing air through said blast tube and fuel spraying means Icomprising a fuel atomizing nozzle located centrally of and adjacent the end of said blast tube; an end cone mounted in the front end of said blast tube for constricting the air stream being forced therethrough by said blower means and directin-g the air stream through the spray issuing from said fuel atomizing nozzle adjacent the end of said blast tube; means for varying the longitudinal distance between the tip of said fuel atomizing nozzle and the outer edge of said end cone for altering the point of impingement of the air stream and spray comprising a bar extending rearwardly through the blast tube from said end cone, clamping means including a part extending from the rear end of said bar through a longitudinal slot in the lower part of the rear end of said blast tube; and means for maintaining the outer edge of said end cone in a plane normal to the longitudinal axis of said blast tube comprising a longitudinal groove in the bottom of said blast tube within which said bar is located and freely slidable for longitudinal adjustment of said end cone, said groove and said bar having complementary shoulders for limiting the extent of outward movement of said end cone.

ALLEN P. LIVAR. 

